1. It’s a time travel story (with a twist)

Yes, it’s another time travel drama, and if you’re a complete K-drama addict, you probably know the most basic essential in moving from one era to another: that one thing that connects the two worlds. In “Signal,” a powerful walkie-talkie connects a man from the past with someone from the future, and in “Tomorrow With You,” the lead travels in between times via subway train. As you might have guessed from the title, a tunnel connects the old and the modern day in “Tunnel.” The drama’s starting point is the year 1985. Choi Jin Hyuk plays the role of Park Kwang Ho, a detective whose life is in an “almost” happy ending; he just got married to his longtime crush, and he is a well-known legend in his job. All of that changes when he pursues a serial killer responsible for murdering women, and the chase leads them to a tunnel.

What makes “Tunnel” different from the other dramas is that Kwang Ho is stuck in the future with no way to get back. Even going back to the same tunnel doesn’t return him to the 80s, unlike the other two dramas where one can physically crossover or make radio conversations to the past and future in a predictable manner. It seems like he has to solve cold cases and piece together puzzles before he can finally go back to the time where he belongs.

2. Watch out for the appearance of VIXX’s N

Detective Kwang Ho just got out of the tunnel that leads to modern-day Seoul, and before he realizes where he is, a raging car comes out of nowhere, almost killing him. Inside, the driver is VIXX’s N, whose name is Kwang Ho too! This mysterious character comes out of nowhere, distraught with a bloodied face and fear in his eyes. He seems to be in pursuit of someone else. Is he connected to the murder in some way? Why does he have the same name? Will he die or stay alive in the drama? And why is he so damn cute even when his face is all contorted with panic?

3. The detective group is actually really hilarious

When Kwang Ho returns to the police station, something’s amiss. He is fast-forwarded 30 years where all the gadgets are modern and his co-detectives are all different. Luckily, he gets mistaken for a new junior police officer who was supposed to transfer to their unit. Jeon Sung Sik (who looks 30 years older than Kwang Ho) is the only person who recognizes him as his senior from the past police station. They both have to keep his literal past a secret from the others. Korea is very big on hierarchy, order, and respect for ranking, and Kwang Ho is basically considered as a newbie in the modern world. Kwang Ho, who’s basically an ahjussi with years of experience in his field, gets treated as the maknae of the group, and there’s hilarious rudeness all around.

4. Anyone and everyone can be the killer.

It may be a classic case of whodunnit, but the cliffhangers each episode can make viewers think twice about who they suspect the culprit is. Take it from the Korean netizens in online communities who all say that the drama keeps them on the edge of their seats, and that it’s so thrilling that they can’t wait for the next episode. If this were a novel, it would be a page turner. Could it be the fierce professor who teaches criminology? The elegant and fashionable old lady with gray hair? Could it be the cheerful doctor/coroner who inspects the dead bodies? Or the guy who’s always wearing a black hoodie lurking around? It’s always the one who wears the hoodie! Your guess is as good as mine.

5. It’s a good exercise for your brain.

If you need a breather from all the romantic dramas and you’re quite tired of the same plot, then this drama is for you. It can get gritty and scary, yet thrilling and alluring.

6. The detective partners could be your next OTP.

They’re like Tom and Jerry wherever they go, but when it comes to serious business, Kwang Ho and Kim Sun Jae (played by Yoon Hyun Min) are a match made in heaven. And it also helps that they both look like dashing heroes. They get on each other’s nerves, but when they put their heads together, they’re able to move the chess pieces together in order to get close to catching the suspect.

6. Watch Choi Jin Hyuk go through all stages of emotion in this drama.

From being like a puppy in love, to confusion, panic, rage, to being cool and collected, Choi Jin Hyuk shows it all. He is proving to be quite a strong actor, well-deserving the lead role. Watch it and you’ll find yourself going through the same feels too!